Field of the Invention
The present invention relates to a zoom lens and an imaging apparatus. In particular, the present invention relates to a zoom lens appropriate to be mounted on a digital camera, a camera for surveillance, a camera for film making, a camera for broadcasting and the like and an imaging apparatus including this zoom lens.
Description of the Related Art
Conventionally, as a zoom lens, and particularly as a zoom lens appropriate for a camera for film making and a camera for broadcasting, a zoom lens consisting of four lens groups has been widely known. In the zoom lens, the sign of the refractive power of each lens group is, in order from the object side, positive, negative, positive and positive, or positive, negative, negative and positive, and two of the four lens groups move relative to each other during magnification change. Further, a zoom lens in which the number of lens groups that move relative to each other during magnification change has been increased is also proposed. For example, Japanese Unexamined Patent Publication No. 10(1998)-031157 (Patent Document 1), Japanese Unexamined Patent Publication No. 2000-267003 (Patent Document 2), and Japanese Unexamined Patent Publication No. 2009-128491 (Patent Document 3) disclose a zoom lens consisting of five lens groups, and in which the sign of the refractive power of each lens group is, in order from the object side, positive, negative, negative, positive and positive, or positive, negative, positive, positive and positive. Further, Japanese Unexamined Patent Publication No. 10(1998)-268194 (Patent Document 4) and Japanese Unexamined Patent Publication No. 11(1999)-072705 (Patent Document 5) disclose a zoom lens consisting of six lens groups, and in which the sign of the refractive power of each lens group is, in order from the object side, positive, negative, positive, positive, negative and positive.